The general purpose of this study is to examine he effects of a work-site meditation-based stress reduction program on a battery of psychophysiological measures designed to assess central and autonomic processes that underlie emotional reactivity. The most basic prediction is that the stress reduction program will have positive effects on psychological and physiological function. By systematically examining these effects, this study may shed light on the actual biological and psychological pathways by which such methods work. More specifically, using the procedures described in detail in the protocol, we intend to determine the effects of the aforementioned program on influenza and hepatitis A vaccine response.